215.
б) ( p + p²) : (p + p²) =pq+p² : pq+p² = pq+p² * q = 1
( q² q³) ( q) q² q q³ pq+p² q²
216.
б) (c + c) * 1 = (3c+2c) * 1 = 5c * 1 = 5
( 2 3) c² ( 6 ) c² 6 c² 6c
217.
б) (z² + 2z + 1) * t = z²+2zt+t² * t = (z+t)² * t = z+t
(t² t ) t+z t² t+z t² z+t t
218.
б) z-3 (z + z² ) = z-3 (z(3-z)+z²) = -(3-z) (3z-z²+z²) = - 3z
z+3 ( 3-z ) (z+3)(3-z) (z+3)(3-z) z+3